This was a project I did around 2011 for the fun of it, but realized the utility later on. The PirateBox is a project by David Darts which uses a router and USB drive to make a portable local peer-to-peer network. One benefit of the Piratebox is security. Often, a lot of people need a file. Instead of risking USB drive sharing, everyone can connect and download the files from the PirateBox. Additionally, it saves the hassle of gathering email addresses or sending out links to a Dropbox or Google Drive.
The router I used was a TP-Link WR703N, which is a Chinese router that can be obtained cheaply. I was surprised at how small it is. The instructions (http://www.piratebox.cc/openwrt:diy) are great and easy to follow. There is a new version which is a little easier to install than mine was. This project was great for learning about SSH, Linux, and editing files with Vi. Once I was a little more comfortable, I played around with the config files.
Wanting to make it portable, I made a battery pack. I could’ve bought one, but making one seemed a lot more fun. To keep everything from flopping around, I ended up putting some velcro in a cigar box and on the components.
This project ran successfully for years, however I’ve used the router for other projects since then. I’ve never done a test on the battery pack, but it lasts for hours. A lot of heat is generated in the regulator which requires a small heatsink. I have also since experimented with variations (using a portable router with internal battery, a laptop full install, and an Android install).